Assessment Notes

Justification

Costatisporus cyanescens is a sequestrate fungal species known exclusively from its description in 2015 based on collections made in Guyana. The lack of any more records may be a result of under-sampling so it is not possible to determine if this species has a restricted distribution or a small population. Further research and search efforts are needed so C. cyanescens is assessed as Data Deficient (DD).

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Taxonomic notes

This is the type and only species in Costatisporus, established by Smith et al. (2015), based on morphological and molecular data.

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Geographic range

It is known from the Upper Potaro River Basin of Guyana in South America.

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Population and Trends

Further records or search efforts are needed to establish the population size and distribution.

Population Trend: Unknown

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Habitat and Ecology

Costatisporus cyanescens has hypogeous to partially emergent, solitary to scattered fruitbodies. It was found growing on mineral soil or in the humic layer under the ectomycorrhizal trees Dicymbe corymbosa or Aldina insignis, in closed canopy tropical wet rainforest (Smith et al. 2015).

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Threats

Without further research into habitat preferences it is difficult to establish threats for this species.

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Conservation Actions

Targeted search efforts and research into the ecology are needed to establish potential host preferences and determine the population size and distribution for this species.

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Source and Citation

Cunha, S.P. & Gonçalves, S.C. 2025. Costatisporus cyanescens. The IUCN Red List of Threatened Species 2025: e.T266001245A266020104. Accessed on 28 November 2025.

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• Country occurrence